This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. On the basis of encouragement from the ESR community, we presented the 2011 ACERT Workshop on "ESR Microscopy and Its Applications in Biomedical ESR Imaging" this January at the Cornell Main campus in Ithaca . The objective of the workshop was to raise awareness in the biomedical community to the potential of ESR Microscopy, especially in relation to ESR Imaging. Topics included a cross-section of up-to-date ESR Microscopy and ESR Imaging techniques. The workshop included lectures, demonstrations, and "hands-on" experience with the latest ESR Microscopy methods with ample discussions of proposals and plans to integrate the new developments in ESRM with current activities in biomedical ESR Imaging. There were participants from outside of ACERT, ACERT staff members who attended, and 8 outside guest speakers for a total of 30 participants. The invited speakers were: Aharon Blank on "ESR Microscopy - Current Capabilities and Future Directions", Oleg Grinberg on "Climbing to Bio-Med: An Historical Overview", Howard J. Halpern on "The Importance of Understanding the Microscopic Distribution of Trityl Radicals for EPR Oxygen Images", Periannan Kuppusamy on "Molecular and Crystalline Spin Probes Encapsulated in Polymeric Materials for Oxygen Sensing", John Marohn on "Force-Gradient Detection Of Electron Spin Resonance from a Nitroxide Spin Label: A Path to Single-Nitroxide Sensitivity and Applications in Biology", Chang Seok Shin on "Sub-micron Resolution of Pulsed ESR Microscopy and Its Application for Biological/Biomedical Research", Sankaran Subramanian on "Advances in time-domain EPR imaging: Towards slice-selected, globally phase-encoded Echo-based FT-EPR imaging and quantitative in vivo oximetry", and Jay L. Zweier on "New Trityl Probes and their use for Measurement and Imaging of Cellular Oxygenation and Redox State". ACERT was represented by two speakers, Jack H. Freed overviewed "ESR Microscopy at ACERT", and Curt Dunnam talked about "Instrumentation for ESR Microscopy" we are developing at ACERT. The Workshop was considered a success by all participants. Good exchange of ideas occurred between the researchers developing ESR microscopy and those involved in macroscopic medical ESR imaging.